Scale construction.



J. H. A. BOUSHELD.

SCALE CONSTRUCTION.

APPLICATION FILED MAR. 15, 1916.

1 ,229,2 1 5 Patented June 12, 1917.

2 SHEETS-SHEET I.

Elmo/MM J. H. A. BOU SFIELD.

SCALE CONSTRUCTION.

APPLICATION FILED MAR.15.I916.

1,229,215. Patented June 12, 1917.

2 SHEETS-SHEET 2- lllII 7/////// amoeutoz tutor/mug UNITED STATES PATENTOFFICE.

JOHN H. A. BOUSFIELD, OF ST. JOHNSBURY, VERMONT, ASSIGNOR TO E. AND T.FAIR- BANKS AND COMPANY, OF'ST. J OHNSBURY, VERMONT, A CORPORATION OFVER- MONT.

SCALE CONSTRUCTION.

Application filed March 15, 1916.

To all whom it may concern:

Be it known that I, JoHN H. A. Boos- FIELD, a citizen of the UnitedStates of America, residing at St. Johnsbury, in the county of Caledoniaand State of'Vermont, have invented certainnew and useful Improvementsin Scale Construction, of which the following is a specification,reference being had therein to the accompanying drawings.

This invention relates to lever construction for scales, such as trackscales and refers more particularly to a lever construction of the typehaving knife edge pivots.

The main object of the invention is to provide improved means forforming the seats for the knife edge pivots and for clamping the pivotsin position. heretofore been customary in the formation of the mainleverfor railroad'track, or other heavy scales to either cast the, pivots inposition or to core out recesses and fit in the pivots by forging. Sucha construction,

however, lacks; the accuracy or refinement that is desirable in thepresent construction of track scales, and I have therefore providedmeans for accurately machining surfaces on both the pivots and the seatsand for wedging the pivots into position so as to clamp the accuratelymachined surfaces into contact with each other.

In the drawings:

Figure 1 is a side elevational view of a track scale lever embodying myinvention. Fig. 2 is a-top plan view thereof.

Fig. 3 is a cross-section on the line w-m of Fig. 1.

Fig. 4 is an end elevational view of one of the pivots...

Fig. 5 is a cross-sectional view through the pivot seat.

In the particular construction illustrated in the drawings the inventionis shown as applied to the main lever of a track scale. A designates themain lever which is provided with the depending knife edge pivots B andC, and the upwardly extending knife edge pivot .D.

The invention primarily relates to the novel manner of forming the seatsfor these pivots and for holding the latter accurately positioned withintheir seats. As shown in detail-in Fig. 5, the knife edge pivot (such asB) is provided with a machined surface E which abuts against theaccurately ma- Speification of Letters Patent.

It has- Patented June 12, 1917.

Serial No. 84,447.

chined side wall F of the seat G. This seat of the recessed portion hasa vertical face F against which the machined face E of the pivot isforced. For holding the two machined surfaces in contact, I employ aclamping strip J which has an inclined surface K adapted to wedgeagainst the oppositely inclined surface L of the pivot. This clampingstrip is held in position by a cap screw M which has a threadedengagement with the body of the lever so that upon adjusting the capscrew the clamping strip can be forced against the inclined side wall ofthe pivot and willv thus produce a sufficientwedging action to force thetwo machined surfaces E and F tightly against each other.

It will be noticed that clamping strip K does not engage with the bottomof the recess or seat G but is free to wedge tightly against theinclined side of the pivot. As a precaution against end-wise movement ofthe pivots, dowel pins O are employed, but the accurate alinement of thepivots is obtained solely by forcing the machined surfaces together.From the above description it will be obvious that the alinement of thepivots can be maintained with great accuracy in both planes and thatthis advantage is obtained by a comparatively simple and economicalconstruction.

While I have shown and described in detail the pivot B, it is obviousthat the pivots C and D are similarly formed, except in the particularconstruction shown in Fig. 2 only two of the cap screws M are employedfor pivot C, which is of lesser length than are .the pivot members B andD. The invention,

however, is not limited to any particular number or arrangement ofpivots or in an manner except as specified in the appended claims.

What I claim as my invention is 1. The combination with a scale lever,of a plurality of knife-edge pivots therefor, said lever having aplurality of accuratelymachined vertical walls spaced an exact distanceapart and said pivots each having an accurately-machined vertical walladapted to engage the machined wall of the lever, and mechanism forsecuring the pivots in position so that their distance apart isdetermined entirely by the machined walls.

, 2. The combination with-a scale lever, of

a knife-edge pivot therefor, said lever having an accurately-machinedvertical wall and sald pivot having an accurately machined verticalsurface adapted to engage the machined wall of the lever, and means forclamping the machined surface of the pivot into contact with themachined wall of the lever.

3. The combination with a scale lever, of a knife-edge pivot therefor,said lever having a recess adapted to receive the body portion of thepivot, one wall of the recess being provided with an accurate surfaceand the adjacent surface of the pivot also being formed accurately, and.a wedge member adapted to force said accurately-formed surfaces intocontact with each other.

4E.'The combination with a scale lever, of a knife-edge pivot therefor,comprising a base portion and a side formed accurately at right anglesthereto, the opposite side of said pivot being inclined toward the base,and a Wedge member adapted to act upon the inclined surface of the pivotto force the accurately-formed surface of the pivot into contact with anaccurately-formed surface on the lever.

5. The combination with a scale lever, of a knife-edge pivot therefor,said lever having a true vertical surface and said pivot member having atrue vertical surface and an inclined surface, a wedge member bearingagainst the inclined surface, and means for adjusting the wedge memberto bear against the inclined surface of the pivot member and force thevertical surface thereof into contact with the vertical surface on thelever.

6. The combination with a scale lever having a plurality of spacedknife-edge pivots and seats for said pivots having accurately formedwalls spaced a predetermined distance apart, and means for positioningthe pivots by clamping the same against said accurately formed walls.

In testimony whereof I afiiX my signature.

JOHN H. A. BOUSFIELD.

Witnesses:

OSMAR A. ULLRIOH, GEO. R. BALLINGER.

